Organic light-emitting device

Abstract

An organic light emitting device with improved light emitting efficiency, the organic light emitting device includes a substrate, a first electrode arranged on the substrate, a second electrode arranged to face the first electrode, an organic light-emitting layer arranged between the first electrode and the second electrode, an electron transport layer arranged between the organic light-emitting layer and the second electrode, wherein the electron transport layer includes a multi-layer structure that includes at least one first layer and at least two second layers, wherein ones of said at least one first layer and ones of said at least two second layers are alternately stacked, wherein ones of the at least two second layers are arranged at both opposite ends of the electron transport layer, each of the at least two second layers having a lower electron mobility than that of each of the at least one first layer.

What is claimed is: 
     
       1. An organic light-emitting device, comprising:
 a substrate; 
 a first electrode arranged on the substrate; 
 a second electrode arranged to face the first electrode; 
 an organic light-emitting layer arranged between the first electrode and the second electrode; and 
 an electron transport layer arranged between the organic light-emitting layer and the second electrode, wherein 
 the electron transport layer comprises a multi-layer structure comprising at least one of first layers and at least two of second layers, wherein
 ones of said at least one of first layers and ones of said at least two of second layers are alternately and sequentially stacked; 
 ones of the at least two of second layers are arranged at both opposite ends of the electron transport layer; 
 each of the at least two of second layers has a lower electron mobility than that of each of the at least one of first layers; and 
 each of the first layers and the second layers is embodied as the electron transport layer. 
 
 
     
     
       2. The organic light-emitting device of  claim 1 , further comprising a hole implant layer arranged between the first electrode and the organic light-emitting layer. 
     
     
       3. The organic light-emitting device of  claim 2 , further comprising a hole transport layer arranged between the hole implant layer and the organic light-emitting layer. 
     
     
       4. The organic light-emitting device of  claim 1 , further comprising an electron implant layer arranged between the electron transport layer and the second electrode. 
     
     
       5. The organic light-emitting device of  claim 1 , wherein the electron transport layer comprises only three layers. 
     
     
       6. The organic light-emitting device of  claim 1 , wherein the electron transport layer comprises five layers. 
     
     
       7. The organic light-emitting device of  claim 1 , wherein the electron transport layer comprises thirteen layers having a 13-layered structure, wherein the first layer and the second layer are stacked in a sequence of the second layer, the first layer, the second layer, the first layer, the second layer, the first layer, the second layer, the first layer, the second layer, the first layer, the second layer, the first layer, and the second layer. 
     
     
       8. The organic light-emitting device of  claim 1 , wherein the at least one first layer and the at least two second layers are arranged within the electron transport layer, the electron transport layer being bounded by ones of the at least two second layers. 
     
     
       9. An organic light-emitting device, comprising:
 a substrate; 
 a first electrode arranged on the substrate; 
 an organic light-emitting layer arranged on the first electrode; 
 an electron transport layer arrangement arranged on the organic light-emitting layer; and 
 a second electrode arranged on the electron transport layer arrangement, wherein 
 the electron transport layer arrangement comprises a first second layer arranged on the first electrode, a first first layer arranged on the first second layer, and a second second layer arranged on the first first layer; each of the second layers has a lower electron mobility than the first layer; and each of the first layer and the second layers is embodied as the electron transport layer. 
 
     
     
       10. The organic light-emitting device of  claim 9 , the second electrode being arranged on the second second layer. 
     
     
       11. The organic light-emitting device of  claim 9 , further comprising:
 a second first layer arranged on the second second layer; and 
 a third second layer arranged on the second first layer. 
 
     
     
       12. The organic light-emitting device of  claim 9 , the second second layer is comprised of a different material than the first second layer. 
     
     
       13. The organic light-emitting device of  claim 11 , each of the first, second and third second layers being comprised of different materials from each other. 
     
     
       14. The organic light-emitting device of  claim 9 , further comprising a hole implant layer and a hole transport layer arranged between the first electrode and the organic light-emitting layer. 
     
     
       15. The organic light-emitting device of  claim 9 , further comprising an electron implant layer arranged between the electron transport layer arrangement and the second electrode.